
class Panda {
    get [Symbol.toStringTag]() {
        return 'Panda' ;
    }
    toString(){
        return '我是熊猫儿' ;
    }
}

console.log( Object.getOwnPropertySymbols( Panda.prototype ) );
console.log( Object.getOwnPropertyNames( Panda.prototype ) )

let x = new Panda();
console.log( Object.prototype.toString.call( x ) );

let a = new Array();
console.log( Object.prototype.toString.call( a ) );

let o = new Object();
console.log( Object.prototype.toString.call( o ) );

let s = new String( 'hello' );
console.log( Object.prototype.toString.call( s ) );